A typical example of the need for protecting fixtures for surface treatment includes painting interior o exterior surfaces of walls, floors and ceilings of buildings such as found in a dwelling house ("home"). Such surfaces have fixtures mounted partly within and partly upon underlying substrates such as plasterboard, rock lath, wire lath and/or plaster. The fixtures include, but are not limited to, electrical or mechanical service connectors. For example, walls of a home typically have electrical switches mounted so that parts thereof pierce through wall surfaces. Another example includes plug-in type electrical receptacles. Another example includes plug-in or screw-on type sound transmitting and amplifying wall fixtures. A further example includes television transmitting lines having wall connectors. A further example includes telephone line connecting outlets. Even vacuum, air and water service connecting outlet boxes are found in some homes or in commercial buildings such as laboratories
A problem in treating surfaces is that the fixtures are often vulnerable to the treating media. For example, electrical devices are particularly vulnerable to water and solution spray often used to wash surfaces or to remove wall paper. Electrical devices become corroded and plug-in slots are often filled with residual materials which cause short circuits. Such vulnerability extends to sound, telephone and television connecting fixtures.
The fixtures are usually installed in boxes set into surfaces of walls, ceilings or floors and generally include plates which provide day-to-day protection from dust, dirt and occasional splashing. However, it is typically desirable to remove such plates for treatment, such as for painting, because the plates often have ornamental designs, permanent coatings or they are made of a smooth, often glossy, decorative material such as chrome metal, copper or plastic. Accordingly, it is typical to remove the plates for some treatments, such as for painting. When the plates are removed, the internal devices, wires, clip, etc., are exposed and are particularly vulnerable to damage.
Heretofore, it has been customary to protect surface fixtures by painstaking measures, for example, by merely brushing around the mounting boxes. Another measure has been to cover the fixtures with a combination of tape and heavy paper. A further measure has been to paint the surfaces before the vulnerable fixtures are installed.
All of the above measures have problems which are time-wasting and expensive. For example, brushing around such fixtures causes uneven paint distribution and it is time-consuming. Furthermore, brushing is unavailable when a preferred method may include spraying the surfaces. Even when paint is applied with rollers, trying to paint around the fixtures is expensive, time-wasting and causes uneven distribution of paint. Even tape and paper coverings are wasteful and time-consuming. Moreover, one must wait until the paint is fully dried because paint accumulated on tape is often sticky, gummy and otherwise unclean. Such coverings and the materials are also expensive because they are typically wasted and cannot be used for repeated surface treatment operations.
U.S. Design Pat. Nos. 279,860 and 297,396, both issued to Schwalbe, are examples of previously designed paint shields for electrical switch plates. These paint shields are apparently both intended to fit over the external cover of the electrical switch plate. As a result, these devices are rather impractical because they will, of necessity, cover an area of the surface being treated which surrounds the periphery of the external cover. When the paint shield is removed, the area of the surface which it covers will appear as an unpainted ring surrounding the external cover of the fixture. Also, because of the tendency of paint to stick to the shield, some of the paint on the surface is likely to be removed when the paint shield is removed. Therefore, the area immediately surrounding the cover of the electrical switch plate will tend to look unattractive and not properly finished.